| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a developing roller, in which a sufficient low resistance value in an intermediate layer containing a UV-curing resin and carbon black is achieved without causing problems such as peeling of a coating film due to curing failure of the intermediate layer, environmental fluctuations of the resistance value of the roller can be reduced, and thereby, printing quality can be improved. <P>SOLUTION: The developing roller is an elastic roller, which includes successively on an outer circumference of a shaft 1, an elastic layer 2, an intermediate layer 3 and a surface layer 4. The intermediate layer 3 contains 1 part by mass or more of carbon black with respect to 100 parts by mass of a UV-curing resin, and includes a photopolymerization initiator having an extinction coefficient of 2×10<SP POS="POST">4</SP>ml/g cm or more at a wavelength of 254 nm and a photopolymerization initiator having an extinction coefficient of 4×10<SP POS="POST">2</SP>ml/g cm or more at a wavelength of 365 nm. <P>COPYRIGHT: (C)2012,JPO&INPIT |
